<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>尺寸和背景颜色</title>
    <style>
        .box{
            /* width: 100px; */
            width: 100%;
            height: 680px;
            background-color: skyblue;
            background-image: url(/2323.jpg);
            background-size: 100% 100%;
            background-position: center;
            background-repeat: no-repeat;
        }
    </style>
</head>
<body>
    <div class="box"></div>
</body>
</html>